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          <th colspan="3" align="center">DB_ENV-&gt;mutex_set_max()</th>
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            <h2 class="title" style="clear: both"><a id="mutexset_max"></a>DB_ENV-&gt;mutex_set_max()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;mutex_set_max(DB_ENV *dbenv, u_int32_t max);  </pre>
      <p>
        Configure the total number of mutexes to allocate. This method is
        deprecated. The maximum size of the mutex region is now inferred by
        the sizes of the other memory structures, and so this method is no
        longer needed. For example, the cache requires one mutex per page
        in the cache. When you specify the cache size, DB assumes a
        page size of 4K and allocates mutexes accordingly. If your page
        size is different than 4K, you indicate this using
        <a class="xref" href="envset_mp_pagesize.html" title="DB_ENV-&gt;set_mp_pagesize()">DB_ENV-&gt;set_mp_pagesize()</a>. 
        DB will then allocate the proper number of mutexes based on this new page size.
    </p>
      <p>
        You can use this method to override DB's mutex calculation, but
        it is not recommended to do so. 
    </p>
      <p>
         Calling the <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> method discards any value
         previously set using the 
         <a class="xref" href="mutexset_increment.html" title="DB_ENV-&gt;mutex_set_increment()">DB_ENV-&gt;mutex_set_increment()</a> method.
    </p>
      <p>
         The database environment's total number of mutexes may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of
         the entry in that file is a single line with the string
         "mutex_set_max", one or more whitespace characters, and the total
         number of mutexes. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the
         database environment is opened, it will silently overrule
         configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> method configures a database environment,
         not only operations performed using the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
    </p>
      <p>
             The <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> method may not be called after the 
             <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>  method is called.
             If the database environment already exists when 
             <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>  is called, the
         information specified to <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> will be ignored.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp53758488"></a>Parameters</h3>
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                <h4 class="title"><a id="idp53764120"></a>max</h4>
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          <p>
                          The <span class="bold"><strong>max</strong></span> parameter is the absolute
                          number of mutexes to allocate.
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              <h3 class="title"><a id="idp53768784"></a>Errors</h3>
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        <p>
                         The <code class="methodname">DB_ENV-&gt;mutex_set_max()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
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                <h4 class="title"><a id="idp53784360"></a>EINVAL</h4>
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                An invalid flag value or parameter was specified.
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              <h3 class="title"><a id="idp53783280"></a>Class</h3>
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        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
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              <h3 class="title"><a id="idp53782336"></a>See Also</h3>
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        <p>
                     <a class="xref" href="mutex.html#mutexlist" title="Mutex Methods">Mutex Methods</a> 
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